(A group of friends and I just placed an order for collection from a pizza place round the corner. They have a special collection offer for £5 per pizza, and the site is also running an additional 20% off offer if you spend over £30. Consequently I add a few items to get it over that. I receive a phone call a few minutes after placing the order.)

Worker – We have to reject your order. The offer you’ve used isn’t valid.